A Nocardia sp.was found during an initial transmission electron microscopic (TEM) examination to have unusual intracellular bodies (ICB's) which do not appear to have been described previously in the literature. Most intracellular structures within bacteria have been classified as storage granules, a product of membrane invagination (i.e. mesosomes), or vacuoles. In bacteria there are no known intracellular membrane-bound organelles, and all internal membranes are invaginations of the unit membrane. Several microscopic-level examinations of the Nocardia sp. ICB's were initiated in order to determine their overall structure, classification, and internal constitution.Different TEM staining procedures were performed to determine possible molecular components of the ICB. In all of the staining protocols the ICB's showed a lack of electron density similar to the cell wall. Because the ICB's showed no affinity to any stain, it appeared they do not have strong positive charge (phosphotungstic acid), are not protein rich (en bloc uranyl acetate), lack glycogen and are not phosphate or sulphur rich (lead citrate), nor do they contain lipids or ribonucleic acids (osmium tetroxide).
Molecular components of stress-responsive plastid retrograde signaling networks and their involvement in ammonium stress